Dead load is the term structural and mechanical engineers use to describe the weight of all the permanent parts of any structure. Here, "weight" means the downward force the structure exerts on the Earth. Dead load is distinguished from live load by the fact that the live load will change depending on the environment around the structure. Live load can be affected by high winds, people or vehicles traversing the structure, or air pressure.

### Things You'll Need

- Structure blueprints
- Engineering data book

- Calculator
- Ruler

## Video of the Day

Measure the areas of each component of the structure using the ruler on the blueprints. Make a note of these values.

Apply appropriate formulae to calculate the dimensions of the structure's components to work out their volumes. In the case of rectangular components, multiply the length by the width by the thickness. In the case of cylindrical components, multiply the square of the cross-sectional radius of the cylinder by pi, and then multiply the resultant value by the length of the cylinder. Make a note of each of these values.

Multiply the volumes of each of the components by the density of the material out of which the components are made. These data can be found in an engineering data book. This calculation determines the mass of each of the components. Make a note of each of these values.

Add the mass of each of the components. Make a note of this value.

Multiply the sum of the mass of all the components by the gravitational field strength of the Earth, g, which is approximately 9.81 meters per second squared or 32.2 feet per second squared. This final value is the dead load of the structure.